STRUCTURAL PROOF OF TETRAZOLO[1,5-a]QUINAZOLINE DERIVATIVES AND THEIR APPLICATION IN THE SYNTHESIS OF 4-AMINO-2-(1,2,3-TRIAZOL-1-YL)QUINAZOLINES

A. Kalniņa, Ē. Bizdēna, G. Kiselovs, A. Mishnev, M. Turks

Abstract

5-Azidotetrazolo[1,5-a]quinazoline (formally known as 2,4-diazidoquinazoline) undergoes regioselective nucleophilic aromatic substitution with amines at C-5 atom and provides corresponding 5-amino derivatives of tetrazolo[1,5-a]quinazoline. For the first time the molecular structure of the latter tricyclic system is unambiguously proved by X-ray diffraction analysis. Tautomeric equilibrium between tetrazolo[1,5-a]quinazolines and 2-azidoquinazolines permits their use in the copper catalyzed azide–alkyne 1,3-dipolar cycloaddition reaction. In this way a series of 4-(R-amino)-2-(1,2,3-triazol-1-yl)quinazolines were obtained.